You'll kill your gear cables if you wash your bike all the time. I brush off the worst when wet, use a screw driver blade to clean the pulleys on the derailleur and the front sprockets. Wipe the chain clean with a clean rag. Carefully drip some oil on the side of the chain that comes in contact with the sprockets/casette, spin a few times. Wipe the fork legs/shock leg clean with clean rag, very lightly oil the surface and cycle the suspension a few times.
A couple of times a season I clean it. Wet it with the hose, use a sponge with little water, rinse, repeat.
I used to clean it every time, BAD idea. You actually CAN wash a bike to death!!!